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%I #12 Dec 20 2021 05:27:42
%S 1,2,2,3,3,3,3,2,5,5,5,3,7,7,7,3,2,5,11,11,11,3,5,5,7,7,13,13,13,3,2,
%T 17,17,17,7,19,19,19,5,5,11,23,23,23,3,5,13,3,7,7,7,5,11,13,7,29,29,
%U 29,11,31,31,31,3,2,17,37,37,37,5,13,19,5,41,41,41,3,7,11,11,43,43,43,5,17,19,5,23,47,47,47,3,7,13,13,17,11,7,3,53,53,53,19
%N The largest prime factor of the n-th term of EKG-sequence: a(n) = A006530(A064413(n)).
%H Antti Karttunen, <a href="/A304733/b304733.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a>
%F a(n) = A006530(A064413(n)).
%t ekGrapher[s_List] := Block[{m = s[[-1]], k = 3}, While[MemberQ[s, k] || GCD[m, k] == 1, k++]; Append[s, k]];
%t FactorInteger[#][[-1, 1]]& /@ Nest[ekGrapher, {1, 2}, 100] (* _Jean-François Alcover_, Dec 20 2021, after _Robert G. Wilson v_ in A064413 *)
%o (PARI)
%o A006530(n) = if(n>1, vecmax(factor(n)[, 1]), 1);
%o A304733(n) = A006530(A064413(n)); \\ Needs also an implementation of A064413.
%Y Cf. A006530, A064413, A064741, A304734.
%Y Cf. also A251103.
%K nonn
%O 1,2
%A _Antti Karttunen_, May 18 2018
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